Income tax reminders
Most tax deductions and credits are based on calendar year spending. RRSP contribution rules seem to throw people off.
Charitable donations are based on calendar year.
Vehicle expenses
Remember to record your odometer reading at the year end.
Repair costs are based on calendar year
You can claim 15% of the cost of a vehicle you purchase during the year (or 30% of the opening book value for the year) or actual lease costs incurred in the year (subject to cost limits & personal/business use restrictions)